During a series of magnetic recording disk manufacturing operations, a disk's surface is exposed to various types of contaminants. Any material present in a manufacturing operation is a potential source of contamination. For example, sources of contamination may include process gases, chemicals, deposition materials, and liquids. The various contaminants may be deposited on the disk's surface in particulate form. If the particulate contamination is not removed, it may interfere with the proper fabrication of a magnetic recording disk. Therefore, it is necessary to clean contamination from the surface of the disk after various stages in the manufacturing process.
Contamination may be removed using a cleaning machine where one or more disks are placed in a disk carrier and submerged in a cleaning tank containing a cleaning liquid in order to remove the particles from the surface of the disk(s). The disks may be rinsed when the carrier is vertically pulled up out of the cleaning solution in the tank with a steam cleaning solution that is sprayed onto the disks during the pulling action. One problem with such a process is that water droplets may remain on the bottom edges of the disks, due to a lack of drying, that can result in stain marks on the surface of the disks.
One conventional type of disk carrier used in the cleaning process has two side rails and a bottom rail that secure the disks within the carrier. FIG. 1A is a cross-sectional view showing the surface of a disk resting between the rails of the disk carrier with: the left side rail contacting the disk at approximately the 9 o'clock position; the right side rail contacting the disk at approximately the 3 o'clock position, and; the bottom rail contacting the disk at approximately the 5 o'clock position (reference to a clock coordinate system on the face of the disk). FIG. 1B illustrates a portion of one of the rails of such a conventional disk carrier. The rail is formed with a saw (a.k.a., shark) tooth pattern on the side contacting the disks. The teeth of the rail have a sloping, flat top surface of about 1 millimeter (mm) thickness, connecting the front and back surfaces of the rail teeth at right angles. Each disks rests between the opposing sloping, top surfaces of adjacent teeth. One problem with such a tooth configuration is that although the top surfaces are sloping, solution droplets may still become trapped on the flat surfaces of the teeth against which the disk rests. Any trapped solution may result in the above noted staining problem.